Recently, plastic exterior products with diverse colors are becoming increasingly popular for electronic parts, automobile parts and the like, and plastic exterior products with a high quality sense of touch.
Plastic exterior products usually include a plastic resin and a metal to give the appearance of a metal-like texture to the resin, such as discussed in Japanese Patent Laid-Open Publication Nos. 2001-262003 and 2007-137963. The metal-like texture, however, did not appear in an actual experiment, and there is a problem in that a flow mark or a weld line is formed during an injection process.
Japanese Patent Laid-Open Publication No. 1995-196901 gives a metal-like texture by adding a metal microplate to a plastic resin. The metal microplate is obtained by a punching process and has the luster of an average shape ratio (thickness/average particle diameter) of 1/100 to 1/8. This technology, however, also has limitations such as formation of weld line.